\\[-1.8ex] Soil Heterogeneity & $-$0.771$^{***}$ & $-$0.590$^{**}$ & $-$0.661$^{***}$ & $-$0.721$^{***}$ & $-$0.814$^{***}$ & $-$0.852$^{***}$ & $-$0.884$^{***}$ \\ 
  & (0.223) & (0.230) & (0.224) & (0.222) & (0.224) & (0.226) & (0.230) \\ 
\\[-1.8ex]
Observations & 8,983 & 8,983 & 8,983 & 8,983 & 8,983 & 8,983 & 8,983 \\ 
R$^{2}$ & 0.294 & 0.293 & 0.294 & 0.294 & 0.294 & 0.294 & 0.294 \\ 
